Stephen Emery pulled himself slowly down the motorboat's anchor chain, 20 feet to the dark bottom of Florida's Sarasota Bay. Above, choppy waters had made the two-mile ride bumpy and mucked up the water, but as he touched bottom the visibility cleared some, and "there it was,'' he recalled.

The anchor had hooked into a hole in a large concrete dome, one of four settled into the sand, ranging from two to four feet in diameter. Together they made an artificial reef, which was so completely covered by algae, barnacles, soft coral and small sponges that Emery couldn't find the bronze plaque he was looking for.

The plaque bears his twin brother's name. The cremated remains of David Emery, who died at 32 when a drunken driver hit his motorcycle, are in one of those algae-covered concrete domes.

"The growth was phenomenal,'' said Emery, an environmental scientist who made his first scuba dive to visit his brother Dec. 23. "I felt, hey, this isn't too bad. I was near where Dave is. He's part of that reef. And I felt that's where he'd want to be.''

Not long ago, people seemed satisfied to bury their dearly departed in cemetery plots or keep their ashes on the mantel. But as views of death and dying change, more people are thinking outside the box. A growing number believe alternative dispositions such as reef burials could change the face of the burial business.

Last weekend, the Cremation Association of North America's two-day seminar in Las Vegas concluded with a session called "It's Not Your Grandparents' Funeral,'' which included memorial paintings by a company called Eternally Yours that blend the deceased's ashes into watercolors. There were also several "green'' options: Celebration Forest in Idaho will plant and care for a memorial tree and scatter the ashes around its trunk. A "nature preserve'' cemetery in South Carolina buries actual bodies in an ecologically sound way. And people who love the ocean can choose artificial reefs.

"It's a niche type of thing, but the niche is growing,'' said Jack Springer, the association's executive director.

For decades, cremation was the niche. But the percentage of bodies cremated went from less than 7 percent in 1975 to 25 percent in 2000 in the United States, according to the association. Despite the gross abuses discovered last month at Georgia's Tri-State Crematory, cremation rates are expected to rise steadily and top 50 percent in 25 years.

But disposing of a loved one's ashes provides an opportunity to deal with death in a more meaningful way. George Frankel, co-founder of Eternal Reefs, the company that buried Dave Emery's ashes, said people are beginning to consider the impact their remains will have on the environment.

"People want to continue making a difference long after their deaths,'' Frankel said. "They come to the end of their lives searching more and more for what their contribution was, should've been or could be. And then they find an option like ours.''

Based in Decatur, Ga., Eternal Reefs is a spinoff from the Reef Ball Development Group, created in 1992 by a group of ecology-conscious diving buddies who wanted to revitalize endangered coral reefs. Hired primarily by governments, the company has sunk more than 100,000 "reef balls'' in 1,500 locations worldwide to build artificial reefs.

"Each reef ball is designed to last 500 years,'' Frankel said of the grainy gray domes that look like giant whiffle ball halves. Six inches thick and made from marine-grade, pH-neutral concrete, reef balls range from 400 to 4,000 pounds.

But it wasn't until four years ago, when one partner's dying father asked to be buried in an artificial reef, that Reef Balls got into the business of ecologically beneficial burials. The company mixed his ashes with concrete, molded it into a reef ball and sank it off Sarasota -- where, today, it is so overgrown and populated with sea life that it is unrecognizable as a grave site.

Since then, Eternal Reefs has "deployed'' the ashes of nearly 100 people off Charleston, S.C., and Sarasota, at a cost of $850 to $3,200 each. This summer it will begin building memorial reefs off Fort Lauderdale and Marco Island, Fla.

"We provide a place to go, as you'd have in a cemetery, except it's in the water,'' Frankel said. "Our families say they get beachfront property for an eternity.''

Lynne Bryant discovered the Eternal Reefs Web site when seeking a water location where she might sink the urn containing her first husband's ashes. Lee Bryant died from a stroke in 1981, a month after they were married. "We had intended to sail around the world together,'' said Bryant of League City, Texas. "I knew that Lee wanted to be buried at sea.''

Facing state and federal laws that regulate the scattering of ashes, Bryant kept her husband's ashes for 20 years. Last June she watched from a rental boat two miles off Sarasota as Eternal Reefs deployed his remains in a reef ball as she scattered dried flowers from their wedding on the water.

Frankel said state and local governments that normally pay for reef building support the memorial reefs. "We're helping the people make a contribution to the environment,'' he said. "The state gets these reef balls for free. And these are going to be public and recreational reefs that anyone can enjoy.''